1. Field of the Invention
This invention pertains to a road transport vehicle and in particular a road transport vehicle for transporting upright glass plates or glass packets.
2. Description of the Prior Art
A known road transport vehicle is disclosed in DE PS 35 16 914. Each securing device therein consists of a frame structure whose horizontal frame elements run practically over the entire length of the load space. However, the perpendicular frame elements are comparatively short, because the parallel crank gears run the securing devices into the release position far upward into the load space. The horizontal frame elements from the understructure of the transport supports which have hollow profiles of elastic material which are set in the secured position on the outside of the glass plates. The parallel crank gears allocated to each securing device are mounted by their perpendicular base to the vehicle longitudinal support that encloses the load space.
Under these conditions there is a considerable reduction in the vehicle's payload due to the base supports of the gears. On the other hand, immobilizing the glass plates is unsatisfactory due to the limited contact surface of the flexible transport supports on the glass plates. Thus the glass plate packets can execute motions under the influence of transport stresses so that glass plates rub together causing scratching of the plate surface that may ruin the plates.
Another disadvantage arises from using different transport frames. More than one type of transport frame is commonly available for use during a long transition period. Since such transport supports are not able to adapt to a change in the angle of inclination of the glass attributable to using different types of transport frames, each time a different transport frame is encountered may result in an unreliable immobilization of the glass.
In the road transport vehicle disclosed in DE GM 87 17 269 the securing devices on each side of the load space are driven separately by individually powered transport braces with a drive allocated to each. Thus a relatively larger contact surface of the transport brace can be achieved in the secured position and the payload enlarged because the drive and the gearing are located transverse to the load space. The gear consists only of a rotating shaft mounted by a pivot joint to the thrust piston drive articulated with the vehicle longitudinal support. The transport brace's understructure is mounted to the rotating shaft; it supports a relatively flat and broad, elastic or elastomer lining in contact with the glass plates in the transport position.
Articulation of the transport braces means they will have to be mounted mostly in the perpendicular middle of the understructure to keep the transport braces at equilibrium during the motion in the two operating positions of the securing mechanism. But the transport frames are loaded with packets of differing perpendicular dimensions. For floating glass plates, these dimensions can go down to about 1.5 m and then only account for a fraction of half the height of the transport frame. Then the mount of the rotating shaft and thus the force attack point of the thrust piston gear moves over the upper edge of the glass plate pocket. In the transport position the transport braces then pivot inward and damage the upper edges of the glass.
The invention is a transport vehicle of the general design described wherein a reliable immobilization of the load is ensured and, in spite of differing dimensions of the load, damage to the load is not possible.